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981.
The concreteness effect: evidence for dual coding and context availability   总被引:10,自引:0,他引:10  
The term concreteness effect refers to the observation that concrete nouns are processed faster and more accurately than abstract nouns in a variety of cognitive tasks. Two models have been proposed to explain the neuronal basis of the concreteness effect. The dual-coding theory attributes the advantage to the access of a right hemisphere image based system in addition to a verbal system by concrete words. The context availability theory argues that concrete words activate a broader contextual verbal support, which results in faster processing, but do not access a distinct image based system. We used event-related fMRI to detect the brain regions that subserve to the concreteness effect. We found greater activation in the lower right and left parietal lobes, in the left inferior frontal lobe and in the precuneus during encoding of concrete compared to abstract nouns. This makes a single exclusive theory unlikely and rather suggests a combination of both models. Superior encoding of concrete words in the present study may result from (1) greater verbal context resources reflected by the activation of left parietal and frontal associative areas, and (2) the additional activation of a non-verbal, perhaps spatial imagery-based system, in the right parietal lobe.  相似文献   
982.
Four experiments involving 123 university students tested directionality effects in the comprehension of spatial relations, quantified statements, and propositional connectives with a sentence-picture verification task. Presentation of the referents of terms in the statements was separated by 1 s, and presentation order was congruent or incongruent with the order of terms in the statement. Some relations showed faster verification times for congruent display order, others for incongruent display order, and still others showed no directionality effect. The authors proposed a 2-step process model for the construction of semantic representations of relational statements, in which a reference object is established first, and then the second object is attached in relation to it. This theory explains the various directionality effects as a general preference to process information about the reference object before information about the target object.  相似文献   
983.
We have recently reported a correlation between schizophrenialike symptoms and the degree of pseudoneglect in healthy right-handers. We aimed to investigate the effect of familial sinistrality (FS) on this relation. Seventy-six healthy right-handers were divided into four groups on the basis of gender and FS. A computerized version of Corsi's task was used as the visuospatial task. Subjects filled in the Magical Ideation Scale (MI), which asked for delusionlike beliefs, and performed the Corsi's task using each hand. Performance of both hemispaces was separately evaluated. In all groups, performance of the left hemispace was better than that of the right hemispace and FS+ subjects performed better than FS- subjects. When the right hand was used, performance was correlated to MI scores only for FS- groups. Findings suggest that the correlation between right-sided neglect and proneness to schizotypy in normal right-handers is affected by FS.  相似文献   
984.
For two-choice tasks in which stimulus and response locations vary along horizontal and vertical dimensions, the spatial compatibility effect is often stronger on the horizontal than vertical dimension. Umiltà and Nicoletti [(1990) Spatial stimulus-response compatibility (pp. 89–116). Amsterdam: North-Holland] attributed this right-left prevalence effect to an inability to code vertical location when horizontal codes are present simultaneously. Hommel [(1996) Perception & Psychophysics, 43, 102–110] suggested instead that it reflects a voluntary strategy. This study reports four experiments that examine this issue. Experiment 1 was a conceptual replication of Hommel's Experiment 1, with responses made on a numeric keypad and subjects instructed in terms of the vertical or horizontal dimension. The results replicated Hommel's findings that showed a right-left advantage with horizontal instructions; however, with vertical instructions, we found a benefit of vertical compatibility alone that he did not. This benefit for vertical compatibility alone was eliminated in Experiment 2 using a varied practice schedule similar to that used by Hommel. Experiment 3 showed right-left prevalence and a benefit of vertical compatibility alone, even with varied practice and vertical instructions, when subjects responded on perpendicularly arranged handgrips. These benefits were eliminated in Experiment 4 using Hommel's method of urging subjects to respond only in terms of the instructed dimension. With bimanual responses, right-left prevalence is a robust phenomenon that is evident when comparing across vertical and horizontal instructions and, when the right-left distinction is relatively salient, within the vertical instructions condition alone. Received: 4 February 2000 / Accepted: 5 May 2000  相似文献   
985.
Wilson JA  Robinson JO 《Perception》2000,29(7):843-851
In exploring stereokinesis, we devised flat cycloidal display figures which, when rotated on a disc in the frontal plane, are perceived as illusory three-dimensional forms with movement in depth; the dominant percepts were of twisted loops with an internal writhing motion. These dominant forms could be convincingly represented by stereo pairs derived from the flat display; related forms, not seen in the illusion, could also be constructed, seeming to show a selectivity for preferred stereokinetic forms by the perceptual system. Models were made of the stereo forms; when rotated, they showed similar illusions and selectivity. We suggest that the illusions arise because some components of the real motion do not appear in the sensory field. The perceptual system accommodates for this by constructing percepts which are not necessarily veridical but do reconcile form and motion into a coherent unity. The results are discussed in relation to concepts of invariance and rigidity, and with regard to the creative response to sensory data by the perceptual system.  相似文献   
986.
The development of object permanence was investigated in black-billed magpies (Pica pica), a food-storing passerine bird. The authors tested the hypothesis that food-storing development should be correlated with object-permanence development and that specific stages of object permanence should be achieved before magpies become independent. As predicted, Piagetian Stages 4 and 5 were reached before independence was achieved, and the ability to represent a fully hidden object (Piagetian Stage 4) emerged by the age when magpies begin to retrieve food. Contrary to psittacine birds and humans, but as in dogs and cats, no "A-not-B error" occurred. Although magpies also mastered 5 of 6 invisible displacement tasks, evidence of Piagetian Stage 6 competence was ambiguous.  相似文献   
987.
Confirmatory factor analysis and regression analyses of the Beavers Interactional Scales did not appear to support the model offered by its developers, namely, several specified family attributes contributing respectively to two global factors of Family Competence and Family Style. Moreover, regression analysis indicated that only three of 12 items predicted raters' assessments of Global Family Health, and one of seven items predicted Global Family Style. Individuals interested in the family dynamic centripetal/centrifugal might best think of that as a unitary entity and rate it accordingly.  相似文献   
988.
989.
990.
Conclusion Controversy still flames around Alinsky. Its very heat makes a cool appraisal difficult. But the heat is also on the Church to forge a fair estimate of Alinsky's goals and tactics. This paper has presented the therapeutic perspective as an important element in that evaluation. It has demonstrated that striking parallels exist between Alinsky's approach to community problems and the psychotherapist's approach to individual problems. It has shown that much of what Alinsky does is psychologically sound. Nor is such a comparison alien to Alinsky's view of his own work. His own commitment to mental health is expressed in a speech:Those concerned with the mental health of our population must bear in mind that these slums and segregated ghettoes operate as enormous breeding grounds for mental pathology and psychoses on a mass basis. They are to mental disease as the swamps were to malaria. It is for this reason that this address has concentrated upon citizen action to the end of ridding ourselves of these conditions which inevitably result in mental disease.It seems distinctly possible that in Saul Alinsky the Church has an obstinate but valuable ally in the search for wholeness and health in individual and community life.  相似文献   
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